Improvement in machines for making chair-seats



UNITED STATES PATENT OFFICE.

EZEA nANsoM, oF ELINT, MIcHIGAN.

Specification forming part of Letters Patent No. 50,955, dated November14, 1865.

To all whom it may concern:

Be it known that I, EZRA RANsoIvLof Flint, in the county of Genesee andState of Michigan, have invented anew and useful Improvement in Machinesfor Making Chair-Seats; and l do hereby declare that the following isafull, clear, and exact description thereot`,which will enable othersskilled in the art to make and use the same, reference being had to theaccompanying drawings, forming part of this specification, in which-Figure 1 is a side view of a machine made according tomy invention. Fig.2 is a plan view thereof. Fig. 3 is a sectional view of part of themachine, taken on the lineas of Fig. l. Fig. 4 is a sectional view takenonthe line y of Fig. 1.

Similarletters of referenceindicate like parts.

This invention has for its object the cutting out or hollowing thewooden bottoms of chairseats by machinery'which is automatic in itsmovements, the wooden blank being moved forward by the revolution of ascrew-thread shaft and sectional nut, the latter being fast on thecarriage which supports the wooden blank, and being disengaged from thesaid shaft by means of the movement of the carriage itself'.

'lhe letter J designates the frame which supports the machinery to bedescribed.

B B designate two ways, which are placed on the top ofthe frame, and areadjustable laterally thereon by means of their slotted arms It, whichextend inwardly along the end pieces of the frame, as seen in Fig. 2.One of the ways is grooved along its inner face, as seen in Figs. 3 and4, and the other is plain.

(l designates a carriage, which travels along said ways, one of itssides having a tongue, which projects into the groove of the way B', andthe other side being supported on the opposite way, B, by means of abracket, c, extending therefrom over said way, said brackets carryingtwo springs, E4 E, one of which is secured to the top of the bracket,and the other to its lower side, so that the free end of the latterrests on the top of a pattern, N, xed on the top of the way B', and theother projects upward against a pattern, N, secured adjustably over thepattern Nl by means of screw-bolts r1', whose ends are hooked over saidpattern N. It results from this construction that when the carriage ismoved toward the right the bracket c, with its springs E E, which areits bearing-surfaces, is compelled to conform to the path marked out forit by the patterns N N. The carriage G has wooden pieces t t, securedbeneath its sides, one of which is made wide, so as to uphold the backpart of the wooden blank O which is to be operated upon.

.Q is a wooden piece bolted by screw-bolts to the inner face of theforward part of thecarriage, and Q is a wooden piece fixed to the frontof a metallic follower, P, by means ot' which the chair-seat 0 isclamped in the carriage. The follower is advanced and with` drawn bymeans of a screw-rod, D, whose outer end is, in this example, formedinto the shape of a crank, for convenience in handling.

A stop, I, is placed on the way B', for the purpose of stopping themovement of the carriage, as hereinafter explained, and it is adjustablethereon, beingin the form of a clamp, which is fastened ou the said wayby a setscrew.

F is a lever, pivoted on the back part of the carriage U, its inner end,which has a hook thereon, being pressed toward the left by a spring, E',so as to hook upon the upper end of a sectional nut, G, when the latteris brought within its reach. rlhe sectional nut G is seen most plainlyin Fig. 3. It is pivoted to the lower end of an arm, d, hanging downwardfrom the back end of the carriage U, and extends upward on theright-hand side of the screw-shaft M, its upper end reaching above thelevel of the carriage, so that it can be engaged by the hooked end ofthe lever F. It is pulled away from the screw-shaft by a spring, E2, astop, 1, being fixed on the end of the carriage to limit its backwardmovement. The forward end of the screw-shaft is supported in acrosspiece,V, extending from side to side of the frame J, and its rearend runs in a bearing, YV, placed on the rear end of the frame. Abevel-gear, L, on the hinder end of the shaft, engages with anotherbevel-gear, L, on a driving-shaft, S, whose outer end carries aband-pulley, K.

A A are revolving cutters, secured to collars pp, which are xed on ashaft, f, that revolves in bearings in the frame J. One end of theshaftf extends beyond the frame and carries a band-pulley, g, by whichthe knives are revolved. H is a strip of met-al, sustained on the insideof the frame beneath the front of the seat to be cut by means of twoscrewrods, a, which work in brackets b b, extending from the frame. Itcan be adjusted to differ-- ent heights.

It will be observed that the carriage Gis capable of supporting seats ofdiierentforms, their back ends being supported on one ofthe wooden restst. (Seen in Fig. 4.)

The patterns N N determine the form of the cut made by the knives, thedepth of the cut being regulated by the thickness of the pattern N.

The front of the seat is made to rest on the step H while itis beingadjustedin the carriage.

When the seat is properly adjusted for the depth of cut required it issecured in the carriage by means of the screw D and follower P.

The wooden blocks Q, Q', which are in immediate contact with the sidesof the seat,

should have sharp points extending therefrom to engage the seat andassist in holding it steady when passing over the knives.

The spring E, which rests on the lower part,

N', is governed7 as to the degree of compression that can be given toit, by the screw-rod `s, which screws down through the bracket c,

its point coming in contact with the free end of the spring, so as toprevent its further compression when they meet each other. The rod s isto be adjusted so as to fix the adjacent side of the carriage at theproper height for the depth of cnt to be made on the seat, and thescrew-rods fr r, which'hold the upper pattern, N, are then screwed downso as to bring `that pattern snugly upon the uppers pring, E4.

bring the outer end of the locking-lever against the adjustable stop Ithe said lever will be disengaged from the head ofthe nut G, whosespring` E2 will then draw it out of engagement with the screw-shaft. Thescrew-bolts r r, or

one of them, being now partially raised, the lower spring, E, will raisethe carriage C so that the knives will not hit the seat when the'carriage is drawn backward over the ways.

satisfactory manner.

One of the objects in having the upper spring, E4, as a bearing for theupper pattern, N, instead of having a solid surface for it to rest upon,is that the upper spring is designed to be the stronger, and it willtherefore compress the lower spring, E, without itself1 beingcompressed, so that when the upper pattern is brought down upon theupper spring hard enough to compress it a trile the lower spring will becompressed sufficiently to `bring it against the end of the set-screw swhile the carriage is passing forward between the ways B B.

Another object is to provide against injurions results to the work if avariation exists between the two parallel patterns. In such a Y case theupper spring, E", being the stronger,

will force the lower spring to conform to the pattern without leavingits support against the set-screw. By this means the carriage G isprevented from vibrating, in consequence lof any such variation betweenthe patterns, and the execution ofthe work will be effected in a Thisset-screw s can be used, to a certain extent, in governing the depth ofthe out on the back end of the seat in case the lower pattern should notbe exactly the right thickness.

The sectional nut G is part of a circle described from the center ofthegroove made in the way Bf, and is therefore concentric with a circledescribed from the same point and passing through the center of thefeed-screw shaft M. Therefore the rise and fall of the carriage on thepattern cannot disen gage the nut from the feed-shaft.

The knives may be of any suitable form, and may be changed by removingone set from the collar 1J and bolting on another set.

Having thus described myinventon, I claim as new and desire to secure byLetters Patentv In a machine for making chair-seats, the arrangementconsisting of the parallel formers N N', actuating vertically one sideof the carriage G upon the axis formed in the sideway B, the carriagemotion being derived from a feed-screw, M, traversing in the sectionalnut G, which is released by the contact of the lever F with theadjustable stop I, as described and'represented. y

EZRA RANSOM.

Witnesses:

N. HYDE, EDMUND D. BARLow.

